The Worldwide Interoperability for Microwave Access (WiMAX) is a wireless metropolitan area network (MAN) technology based on the IEEE 802.16 standard. A WiMAX network is mainly formed by three parts, that is, a mobile subscribe station/subscribe station (MSS/SS), an access service network (ASN), and a connectivity service network (CSN). The ASN includes a BS and an ASN-gateway (ASN-GW). The CSN includes a prepaid server (PPS), an authentication, authorization and accounting server (AAA server), and other logical entities.
In the prior art, in order to realize mobility restriction of an MS, the MS users are divided into three categories, namely, fixed users, nomadic users, and mobile users.
A reattaching method for a fixed user or nomadic user when accessing a network is shown in FIG. 1, which includes the following steps.
In step 1, an MS accesses a BS, and requests a relevant service.
In step 2, the BS requests a BS controller (BSC) to authenticate the MS user, and meanwhile transfers a BS identifier (BSID) and a reattachment zone of the BS.
In step 3, the BSC queries MS user associated information through an AAA server.
In step 4, the AAA server sends MS user subscription information to the BSC. The MS user subscription information includes mobility restriction information and information indicating whether the MS user (the MS user is a fixed user/nomadic user) needs to maintain session continuity.
In step 5, upon successful authentication, the BSC notifies the BS of the successful authentication and performing session establishment.
In step 6, the BS completes the session establishment and notifies the MS of successful network access.
In the implementation of the present invention, the inventor(s) found that the prior art at least has the following problem. Currently, in the reattachment of an MS, the BS accessed by the MS is not restricted during the handover process, so that the requirements for mobility restriction of the MS cannot be satisfied.